The first important point is that the difference itself is not a diagnosis. One person might want sex three times a week and another once a week, and there is no universal referee who can declare one of them “normal” and the other “wrong.”
It becomes a problem when the discrepancy creates distress.
The higher-desire partner may begin to experience repeated rejection. The lower-desire partner may experience pressure, guilt and the sense that their body is expected to provide regular proof of love.
Then an unpleasant kind of arithmetic begins: “I initiated five times and you only did once.” “We used to have more sex.” “Normal couples have sex X times per week.”
But frequency alone tells us surprisingly little. Two people may have sex rarely and both be completely satisfied. Another couple may have sex much more often and still live in chronic conflict around desire.
Are both of us satisfied with our sexual life? If not, can we talk about the difference without one person constantly experiencing rejection and the other having sex out of obligation?
Sometimes sexual compatibility does not mean wanting sex equally often. It means being able to live safely with the fact that sometimes you want different things.
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